import java.util.Scanner;

public class text6 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        double height = sc.nextDouble();
        double paper = 0.1;
        int count = 0;
        while (paper  <= height) {
            paper *= 2;
            count++;
        }
        System.out.println(count);
    }
}
